In the subsidized energy business, not agriculture

Two Chilmark farms were recently granted permits for large-scale wind turbines, under a presumed agricultural use exemption. Abutters have asked the zoning board of appeals to review the permits, calling for more thought and a public process.

Current Chilmark zoning bylaws prohibit the zoning board of appeals from issuing special permits for such turbines over an abutter’s objection — and/or if the turbine does not “preserve and enhance existing . . . natural features, as well as vistas, water views and historic locations . . .”

Clearly then, the decision of the board as to whether these turbines qualify under the agricultural exemption is a make-or-break decision, at least for now, with impacts to be felt by the community at large.

Drive down to Lucy Vincent Beach and look back at the Allen Farm’s meteorological pole rising 165 feet above the pasture; look at it from the cemetery. Imagine the Grey Barn turbine from the Tisbury Great Pond shore.

The agricultural exemption is offered to “structures . . . for the primary purpose of commercial agriculture,” legally understood as distinguishing such from “residential purposes” of the farm property. Legal opinion notes a lack of precedent and statutory guidance on a more precise definition of the qualifying criteria, suggesting a need to turn to common sense or “everyday definitions of the term” for further interpretation.

Looking at what we’re told about the first of the Vineyard turbines to go up under such an exemption (at Morning Glory Farm in Edgartown), none of the electricity generated is used on the farm; it all goes into the grid; the farm continues to draw all the energy it needs, when it needs it, from the grid.

The Endurance 3120 turbine proposed by the Allen Farm in Chilmark is designed to send energy to the grid. And why would the private owners do otherwise? Any kilowatts they keep on the farm simply reduce what they would purchase from the grid. (My current bill puts the generation charge at $.095 per kilowatt-hour.) But for every kilowatt Morning Glory Farm sends to the grid, they’re paid at a substantially subsidized higher rate (currently about $.24 per kilowatt-hour); the first year they get an additional $.88 per kilowatt-hour production incentive. Then the farm takes back what they need (smoothed, usable, on-demand power) at the going rate of $.095 per kilowatt-hour.

Such a deal. Paid for by you and me, the ratepayers, after we taxpayers and ratepayers have subsidized the turbine research and development, manufacture and installation.

Should the above net metering opportunity (“running the meter backwards”) redefine the qualifying criteria of the old statute, adopted before such large-scale turbines were developed? Energy sold to the grid isn’t energy used on the farm. There are winners and losers in this debate. We shouldn’t let sloppy thinking favor one side or another.

Is there an outside benefit from these miraculous new machines that sweep up taxpayer dollars and user surcharges to deposit them in private pockets? Marketing says yes. Science says no.

No matter how many turbines are out there to “contribute” energy to the grid, we always need an absolute level of back-up power available for when the wind doesn’t blow, or blows too hard, or when the turbines are stilled by mechanical failure — which happens a lot.

Turbines can never be more than a purely redundant power plant. But it’s worse than that.

ISO-New England is the nonprofit entity tasked with managing the New England grid system. Since electricity cannot be stored, this requires a continuous and instantaneous balancing of supply and demand. Science performs wizardry — predicting consumption across time of day and season, varying with the weather or a delayed ball game.

At the macro level, to ensure adequate supply, demand is forecast a year in advance; and to meet their customers’ needs, the nation’s 10 regional electrical “grids” forecast minute-to-minute demand with 99 per cent accuracy, in real-time. ISO-NE takes the pulse of the Northeast power grid every four seconds.

A wind turbine’s output is unpredictable, one year or one hour in advance, and varies continuously, always skittering, extremely sensitive to small changes in wind speed. I’m told that since “wind power is proportional to the cube of the wind speed,” small changes in wind velocity affect output enormously. Who knew?

Underscoring this, manufacturer specs on the E3120 show that a 50 percent decrease in wind speed from 18 to 9 miles per hour decreases power output by 93 percent, from 35.8 kilowatts to 2.2 kilowatts. A decrease in wind speed from 27 to 13 miles per hour reduces output by 73 percent: 57.3 kilowatts down to 15.2 kilowatts, assuming I’ve done the math correctly. Of course, excessive wind shuts down power output altogether for safety concerns.

As the level of wind energy flutters about the grid, rising and falling at random, rapidly responsive conventional generators are deployed to balance this ebb and flow. When intermittent wind power comes in (largely off-peak and off-season), the conventional plant is cut back (with energy shed in the process), then ramped up (using energy to get back to a level to help out again). The inefficiencies entering the system are enormous.

While we might have hoped that wind energy could result in reduced fossil fuel consumption and greenhouse gas emissions, recently accumulating data from around the world shows conclusively that such reductions are miniscule at best, and often result in increased fuel usage and CO2 emissions due to the inefficiencies introduced into the system, not to mention the CO2 emissions and fuel consumed in the manufacture, transportation, construction, and maintenance of the turbines and their infrastructure.

So how could, and why should, the Chilmark zoning board of appeals make a ruling that defies a common sense reading of the phrase “for the primary purpose of commercial agriculture”? Stranger things have happened.

We can hope that they will make their decision based on facts, not fantasy, without redefining clearly established intent in favor of one party or another.

And if the zoning board of appeals upholds the agricultural exemption, we can hope for a wiser decision upon appeal.